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The Abdominal Wall An Overlooked Source of Pain American


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The Abdominal Wall:
An Overlooked Source of Pain
University of New Mexico School of Medicine, Albuquerque, New Mexico

When abdominal pain is chronic and unremitting, with minimal or no relationship to
eating or bowel function but often a relationship to posture (i.e., lying, sitting, stand-
ing), the abdominal wall should be suspected as the source of pain. Frequently, a local-
ized, tender trigger point can be identified, although the pain may radiate over a dif-
fuse area of the abdomen. If tenderness is unchanged or increased when abdominal
muscles are tensed (positive Carnett’s sign), the abdominal wall is the likely origin of
pain. Most commonly, abdominal wall pain is related to cutaneous nerve root irritation
or myofascial irritation. The pain can also result from structural conditions, such as
localized endometriosis or rectus sheath hematoma, or from incisional or other
abdominal wall hernias. If hernia or structural disease is excluded, injection of a local
anesthetic with or without a corticosteroid into the pain trigger point can be diagnos-
tic and therapeutic. (Am Fam Physician 2001;64:431-8.)

                                                  he abdominal wall as a           true if the pain is not progressive and if
                                                  source of pain has received      no evidence of visceral disease is present.
                                                  little attention, and only a        Certain features may point to a pain
                                                  few reviews on the topic         source in the abdominal wall (Table 2).
                                                  have been published in the       Unlike pain that originates in the digestive
                                    past decade.1,2 However, physicians who        tract, pain from the abdominal wall is not
                                    consider abdominal wall pain in their          made better or worse with food and is not
                                    patients often find it. In fact, overlooking   altered by bowel movements. Further-
                                    the abdominal wall as a source of pain         more, abdominal wall pain is often
                                    can result in a prolonged, expensive,          chronic, nagging and nonprogressive. An
                                    frustrating and dangerous evaluation.

                                    Evaluation                                     TABLE 1
                                       In patients with acute or chronic           Some Features
                                    abdominal pain, a number of clinical           of Intra-abdominal Pain
                                    findings point to disease inside the ab-
                                    domen (Table 1). When such findings are        Nausea, vomiting, weight loss
                                    absent, consideration should be given to       Diarrhea, constipation or change in bowel
                                    the abdominal wall as the source of pain.        habits
                                       In chronic abdominal pain, the ab-          Pain not made better or worse by eating or
                                                                                     bowel movements
                                    dominal wall often can be implicated
                                                                                   Jaundice or other liver function test
                                    based on the findings of the history and         abnormalities
                                    physical examination. This is especially       Bleeding or anemia
                                                                                   Laboratory evidence of inflammation*
  Pain that is the same or increased when the abdominal wall is
                                                                                   *—Elevated white blood cell count, sedimen-
  tensed generally indicates an origin in the abdominal wall.                      tation rate or C-reactive protein level.

AUGUST 1, 2001 / VOLUME 64, NUMBER 3                       www.aafp.org/afp                  AMERICAN FAMILY PHYSICIAN     431
                                                                                           trigger point in the right upper quadrant
TABLE 2                                                                                    (nerve root T7) can refer pain to the angle of
Some Features of Abdominal Wall Pain                                                       the scapula. Patients are often so preoccupied
                                                                                           with the large area of pain spread that they do
Pain often constant or fluctuating; less often, episodic                                   not realize the area of tenderness is extremely
Pain intensity possibly related to posture (e.g., lying, sitting, standing)                localized and superficial.
Pain not related to meals or bowel function                                                   Several studies have demonstrated the value
No findings of an intra-abdominal process (see Table 1)                                    of the physical examination in the diagnosis of
Abdominal tenderness unchanged or increased when abdominal wall is tensed                  abdominal wall pain. Investigators in one
  (positive Carnett’s sign)                                                                study3 found that of 120 emergency depart-
Discrete, tender pain trigger point no more than a few centimeters in diameter             ment admissions for acute abdominal pain,
Trigger points often found along lateral margins of the rectus abdominis                   23 of 24 patients with a positive Carnett’s sign
  muscles or at attachments of muscle or fascia                                            had a normal laparotomy. In another study4 of
With stimulation of trigger point, referral of pain or spreading of pain over a            72 patients with obscure, chronic abdominal
  large area
                                                                                           pain and a positive Carnett’s sign, two patients
                                                                                           were found to have pain related to spinal
                                                                                           metastases from recurrence of known gyneco-
                              algorithm for the diagnosis and management                   logic malignancies; otherwise, when com-
                              of abdominal wall pain is provided in Figure 1.2             bined with other information from the his-
                                 Tenderness originating from inside the                    tory and physical examination, a positive
                              abdominal cavity usually decreases when a                    Carnett’s sign was found to be a reliable pre-
                              supine patient tenses the abdominal wall by                  dictor of abdominal wall pain.
                              lifting head and shoulders off the examining                    Investigators in yet another study5 pros-
                              table. In contrast, pain originating from the                pectively evaluated patients with chronic
                              abdominal wall is unchanged or increased by                  abdominal pain who met minimal criteria for
                              this maneuver (positive Carnett’s sign).3-5                  abdominal wall pain. Criteria included a pos-
                                 A tender trigger point in the abdominal                   itive Carnett’s sign or very superficial tender-
                              wall is frequently no more than 1 or 2 cm in                 ness combined with pain that was constant or
                              diameter. However, it is not unusual for the                 highly localized to an area no larger than a fin-
                              pain to spread over a wide area or to be                     gertip. Four patients proved to have visceral
                              referred. For instance, pressing on a tender                 disease (esophagitis, bile duct stricture, diver-
                                                                                           ticular disease and visceral neuropathy); these
                                                                                           patients did not respond to the injection of a
                                                                                           local anesthetic. Of the 79 patients in the
The Authors                                                                                study, 72 (91 percent) experienced at least
SAUD SULEIMAN, M.D., currently has a private practice in gastroenterology in               50 percent pain relief with one injection of
Lewisville, Tex. Dr. Suleiman graduated from Damascus University School of Medicine,       local anesthetic, and at least 56 patients
Syria. He completed a residency in internal medicine at Mercy Hospital Medical Cen-        (78 percent) had permanent relief with one or
ter, Chicago, and a fellowship in gastroenterology at the University of New Mexico
School of Medicine, Albuquerque.                                                           two injections. Thus, when combined with
                                                                                           other clinical criteria, a positive Carnett’s sign
DAVID E. JOHNSTON, M.D., currently is a gastroenterologist at The Everett (Wash.)
Clinic. Previously, he was on the faculty of medicine at Tufts University School of Med-   is valuable as a sign of abdominal wall pain.
icine, Boston, and the University of New Mexico School of Medicine. After graduating
from the University of Pittsburgh School of Medicine, Dr. Johnston completed a resi-       Identifiable Causes
dency in internal medicine at Brigham and Women’s Hospital, Boston, and a fellow-          HERNIAS
ship in gastroenterology at New England Medical Center, also in Boston.
                                                                                             In addition to the familiar inguinal, femoral
Address correspondence to David E. Johnston, M.D., Gastroenterology, The Everett
Clinic, 3901 Hoyt Ave., Everett, WA 98201-4988 (e-mail: djohnston@everettclinic.           and umbilical hernias, a number of unusual
com). Reprints are not available from the authors.                                         hernias can occur (Figure 2). Among these are

432    AMERICAN FAMILY PHYSICIAN                                www.aafp.org/afp                     VOLUME 64, NUMBER 3 / AUGUST 1, 2001
     The rightsholder did not grant rights to reproduce this item in
     electronic media. For the missing item, see the original print
     versionof this publication.

FIGURE 1. An algorithm for the diagnosis and management of abdominal wall pain.

the epigastric hernia in the upper midline and       becomes incarcerated in a hernia, severe pain
the more subtle spigelian hernia of the poste-       can occur without bowel obstruction.
rior lateral abdominal wall fascia, at the edge of
the rectus sheath, which occurs in the mid-          Illustrative Case
abdomen. Herniation of bowel loops often                A 55-year-old woman presented with multi-
causes visceral pain with vomiting and bowel         ple episodes of right upper quadrant abdomi-
obstruction. However, when only omentum              nal pain over the course of one year. The
                                                                                               Linea alba

                                                   Lateral cutaneous                                                                                             Epigastric
                                                   branches of                                                                                                   hernia
                                                   intercostal nerves

                                                       Anterior cutaneous
                                                       branches of                                                                                    Posterior layer
                                                       intercostal nerves                                                .                            of rectus sheath

                                                     Lateral cutaneous                                      .                                        Umbilical hernia
                                                     branches of                      ..
                                                     subcostal nerve
                                                                                               .                             ..
                                                                                                                                                     Arcuate line
                                                        Lateral cutaneous
                                                        branch of                                                    .                              Spigelian hernia
                                                        iliohypogastric nerve
                      ILLUSTRATIONS BY TODD BUCK

                                                                                                                                       Inferior epigastric vessels
                                                                   Anterior cutaneous
                                                                   branch of subcostal nerve
                                                                                                                    Rectus abdominis muscle (cut)

                                                   FIGURE 2. Locations where pain in the abdominal wall might originate. Epigastric hernias occur
                                                   along the linea alba. Spegelian hernias occur below the arcuate line where the inferior epigas-
                                                   tric vessels traverse the fascia. Nerve roots passing through or around the lateral edge of the rec-
                                                   tus sheath are often subject to irritation.

                                                   episodes were separated by months during                 tectomy. An abdominal CT scan was initially
                                                   which she felt well. Each episode started                read as normal, but review of the scan showed
                                                   abruptly, without warning, and without a rela-           herniation of omentum through a defect in
                                                   tionship to food. Previously, she had under-             the abdominal wall near the site of the chole-
                                                   gone computed tomographic (CT) scanning                  cystectomy scar (Figure 3).
                                                   of the abdomen, barium radiography and                     While the patient’s right hip was being
                                                   endoscopy of the digestive tract, and endo-              manipulated during a physical examination,
                                                   scopic retrograde cholangiopancreatography.              her pain abruptly disappeared, along with the
                                                   The findings of these studies were normal.               tender mass. A ventral hernia was diagnosed
                                                      The patient was now admitted with acute               and surgically repaired.
                                                   right upper quadrant pain. A tender, fluctu-
                                                   ant 8-cm mass was felt in the right upper                DISCUSSION
                                                   quadrant, several centimeters inferior to a                As in the illustrative case, the area of tender-
                                                   subcostal scar from a previous open cholecys-            ness in a ventral hernia may lie several cen-

434   AMERICAN FAMILY PHYSICIAN                                                 www.aafp.org/afp                                  VOLUME 64, NUMBER 3 / AUGUST 1, 2001
                                                                                                  Abdominal Wall Pain

timeters to the side of a visible surgical scar.
The physical examination for a hernia should         The physical examination for a hernia should be performed
be performed with the patient both standing          with the patient both standing and supine.
and supine. CT scanning is often useful in the
evaluation of possible hernia, especially in
obese patients.6 However, it is important to
focus the radiologist on the abdominal wall if     NEUROPATHIES
the findings of the history and physical exam-        Herpes zoster can cause pain for days before
ination suggest a problem in this area, because    the onset of vesicles. Painful acute neuropathy
it is not unusual for abdominal wall defects to    of the mononeuritis multiplex type can cause
be overlooked on CT scans.                         sudden, persistent abdominal pain in patients
                                                   with diabetes or vasculitis. Nerve root irrita-
OTHER LESIONS                                      tion may result from the compression of nerve
   Various lesions can cause acute or chronic      roots T7 through L1.14 Nerve root compres-
pain in the abdominal wall. Localized tender-      sion can occur in or near the rectus sheath or
ness often occurs in surgical scars several        can involve the ilioinguinal nerve.15-19
months after surgery because of the forma-            Common causes of abdominal wall pain
tion of neuromas. Endometriosis tends to           are summarized in Table 3.
recur in surgical scars.7,8 Hematomas of the
abdominal wall or rectus sheath can occur          Idiopathic Abdominal Wall Pain
spontaneously or after surgery, trauma or             Many patients present with chronic pain
pregnancy.9,10 Desmoid tumors can also cause       that is not related to an identifiable mechanical
chronic abdominal pain.11 Athletes have been       or physiologic abnormality in the abdominal
found to develop abdominal wall pain related       wall. Dealing with this ambiguous situation is
to myofascial tears or idiopathic intra-           somewhat similar to dealing with nonspecific
abdominal adhesions.12,13                          low back pain, in that the exact structures and
                                                   mechanisms responsible for the pain are often
                                                   not known.
                                                      Pain trigger points frequently seem to lie
                                                   along the lateral margins of the rectus abdo-
                                                   minis muscles (linea semilunaris), where
                                                   cutaneous nerve roots pass around the rectus
                                                   sheath. It has been proposed that cutaneous
                                                   nerve roots can become injured where they
                                                   pass through the abdominal wall, perhaps
                                                   by the stretching or compression of the nerve
                                                   root along its course through the abdominal
                                                      In some instances, a tight belt or other
                                                   poorly fitted clothing can cause nerve root
                                                   irritation, especially in physically unfit per-
                                                   sons with protuberant abdomens. Pain also
FIGURE 3. Abdominal computed tomographic           can occur in or around the abdominal wall
scan showing a defect in the abdominal wall
                                                   where muscles insert on bones or cartilage.
in the right upper quadrant (arrow). In this
patient, omentum had become incarcerated           For example, the pain can occur where the
in a ventral hernia inferior to an old cholecys-   rectus abdominis muscles insert on the lower
tectomy scar.                                      ribs or where the lower ribs connect through

AUGUST 1, 2001 / VOLUME 64, NUMBER 3                   www.aafp.org/afp                     AMERICAN FAMILY PHYSICIAN   435
                        TABLE 3
                        Etiology of Abdominal Wall Pain

                        Etiology                     Comments                                      Diagnosis

                        Hernia                       Protuberance in abdominal wall that           Abdominal CT scanning, abdominal
                                                       usually decreases in size when patient       ultrasonography, herniography
                                                       is supine
                        Rectus nerve entrapment      Occurs along lateral edge of rectus           Injection of local anesthetic
                                                      sheath; worsening of pain with tensing
                                                      of muscles
                        Thoracic lateral cutaneous   Occurs spontaneously, after surgery or        History and physical examination
                         nerve entrapment             during pregnancy
                        Ilioquinal and               Lower abdominal pain that occurs after        History and physical examination
                           iliohypogastric nerve       inguinal hernia repair
                        Endometriosis                Cyclic abdominal pain                         Laparoscopy
                        Diabetic radiculopathy       Acute, severe truncal pain involving          Paraspinal EMG
                                                      T6-T12 nerve roots
                        Abdominal wall tear          Occurs mainly in athletes                     History and physical examination
                        Abdominal wall               Complication of abdominal laparoscopic        Abdominal CT scanning, abdominal
                         hematoma                     procedures                                    ultrasonography
                        Spontaneous rectus           Presents as tender, usually unilateral mass   Abdominal CT scanning, abdominal
                         sheath hematoma               that does not extend beyond midline          ultrasonography
                        Desmoid tumor                Dysplastic tumor of connective tissue;        Surgical excision
                                                      occurs in young patients (females more
                                                      often than males)
                        Herpes zoster                Pain and hyperesthesia followed by            History and physical examination
                                                      vesicles along a dermatome
                        Spinal nerve irritation      Caused by disorders of thoracic spine         CT scanning or MRI studies of
                                                                                                     thoracic spine
                        Slipping rib syndrome        Sharp, stabbing pain in upper abdomen         Hooking maneuver to pull lower
                                                      caused by luxation of eighth to               ribs anteriorly, which reproduces
                                                      10th ribs                                     the pain and sometimes a click
                        Idiopathic                   Myofascial pain                               History and physical examination

                        CT = computed tomography; EMG = electromyography; MRI = magnetic resonance imaging.

                        cartilage. The xiphoid cartilage is sometimes
                        a specific focus of pain.                                 Management
                           Abdominal wall pain can be thought of as               PATIENT EDUCATION AND REASSURANCE
                        one category of myofascial pain. In this situa-             Once a tentative diagnosis of abdominal
                        tion, muscle or fascial strain can lead to a pain         wall pain has been made, it is important to
                        trigger point. The mechanism for the pain may             explain the diagnosis to the patient. The
                        involve the development of an area of hyperal-            patient may be worried about the implications
                        gesia as a result of myofascial stretch injury.20         of the pain. Furthermore, having to undergo a

436   AMERICAN FAMILY PHYSICIAN                        www.aafp.org/afp                       VOLUME 64, NUMBER 3 / AUGUST 1, 2001
                                                                                                     Abdominal Wall Pain

long series of diagnostic tests may reinforce
the patient’s anxiety. In this setting, pain can       A major goal of trigger-point injection is to confirm the
take on a life of its own.                             abdominal wall as the pain source.
  If there is evidence of a benign source of
abdominal wall pain rather than a serious
internal disease, reassurance should be pro-
vided. The physician can demonstrate how             corticosteroid. Steroids presumably reduce
gentle palpation of the pain trigger point can       inflammation or result in the thinning of con-
reproduce the pain and its radiation over a          nective tissue around painful nerve roots.
wide area of the abdomen. The physician                 Only a few tenths of a milliliter of a 1:1 mix-
should explain that idiopathic abdominal wall        ture of 1 or 2 percent lidocaine and triamci-
pain is similar to idiopathic back or shoulder       nolone (Aristocort, in a concentration of 40
pain, in that the involved structure cannot be       mg per mL) is required (in any case, less than
precisely described and the cause of the pain        1 mL), so less than 20 mg of triamcinolone is
cannot be exactly identified.                        used. If the correct spot is injected, the pain
                                                     should be relieved immediately, but it may
TRIAL OF LOCAL ANESTHETIC                            return in a few hours when the effects of the
   Much has been written about the treatment         lidocaine wear off. Triamcinolone may take
of idiopathic myofascial pain.20,21 The trigger      effect slowly over a day or two and then pro-
point for abdominal wall pain can be treated         vide long-term relief.
with injection of a small volume of local anes-         More than one injection may be required,
thetic. Once the patient identifies the trigger      given the hit-or-miss nature of this treatment.
point with one finger, the physician “marches”       Such injections can be used to treat a tender
his or her fingers around the area to identify       trigger point in a surgical scar (a presumed
the center of the tender spot, which is usually      neuroma). If reasonable care is taken, the risks
1 to 2 cm in diameter.                               associated with the injections should be mini-
   A tuberculin syringe with a 5/8-inch needle       mal. Repeated injections or larger doses of the
is then used to inject a few tenths of a milli-      corticosteroid can cause thinning of the fascia
liter of 1 percent lidocaine (Xylocaine) into        and result in a hernia. For this reason, depot-
the most tender spot. A longer needle may be         type steroids should not be used in the fascia.
needed in an obese patient. The trigger point
is identified when the tip of the needle causes      PHENOL
marked tenderness.                                      Permanent pain relief with anesthesia can
   The injection of local anesthetic serves as a     be achieved with injections of phenol into the
therapeutic trial and may not provide perma-         pain trigger point.22 These injections should
nent relief. However, a significant number of        be given by an anesthesiologist or a pain treat-
patients experience pain relief after one or         ment subspecialist. Referral to a subspecialist
two injections.5 A major goal of trigger-point       also may be considered for patients who have
injection is to confirm the abdominal wall as        more generalized pain related to irritation of a
the pain source. In addition, this simple            thoracic or intercostal nerve root.
maneuver can help persuade a skeptical
patient that the abdominal wall is, indeed, the      OTHER TREATMENTS
source of the pain.                                     In addition to injection of medications,
                                                     “dry” needling of pain trigger points without
LOCAL ANESTHETIC AND STEROID                         medication has been used with some suc-
  For more permanent relief of pain, it is often     cess.23 A trial of acupuncture or other alterna-
useful to inject a mixture of local anesthetic and   tive treatment might be considered.

AUGUST 1, 2001 / VOLUME 64, NUMBER 3                     www.aafp.org/afp                      AMERICAN FAMILY PHYSICIAN   437
Abdominal Wall Pain

                          Myofascial pain in the abdomen and else-                4. Thomson WH, Dawes RF, Carter SS. Abdominal
                                                                                     wall tenderness: a useful sign in chronic abdominal
                        where has also been treated using various                    pain. Br J Surg 1991;78:223-5.
                        combinations of massage, physical therapy                 5. Greenbaum DS, Greenbaum RB, Joseph JG, Natale
                        with stretching, and cooling topical anesthetic              JE. Chronic abdominal wall pain. Diagnostic valid-
                                                                                     ity and costs. Dig Dis Sci 1994;39:1935-41.
                        sprays.20 Warm soaks and other local methods              6. Rose M, Eliakim R, Bar-Ziv Y, Vromen A, Rachmile-
                        can be useful.                                               witz D. Abdominal wall hernias. The value of com-
                                                                                     puted tomography diagnosis in the obese patient.
                                                                                     J Clin Gastroenterol 1994;19:94-6.
                                                                                  7. Wolf Y, Haddad R, Werbin N, Skornick Y, Kaplan O.
                          If the distress caused by a patient’s pain                 Endometriosis in abdominal scars: a diagnostic pit-
                                                                                     fall. Am Surg 1996;62:1042-4.
                        seems out of proportion to other findings, the            8. Seydel AS, Sickel JZ, Warner ED, Sax HC. Extra-
                        presence of depression or other psychologic                  pelvic endometriosis: diagnosis and treatment. Am
                        dysfunction should be considered. Pain that                  J Surg 1996;171:239.
                                                                                  9. Edlow JA, Juang P, Margulies S, Burstein J. Rectus
                        would normally be a minor nuisance can                       sheath hematoma. Ann Emerg Med 1999;34:671-5.
                        become the focus of somatization and be                  10. Moreno Gallego A, Aguayo JL, Flores B, Soria T,
                        greatly magnified by depression.                             Hernandez Q, Ortiz S, et al. Ultrasonography and
                                                                                     computed tomography reduce unnecessary sur-
                          A tricyclic antidepressant, given in a low                 gery in abdominal rectus sheath haematoma. Br J
                        dosage that minimizes sedation and anticholin-               Surg 1997;84:1295-7.
                        ergic side effects, can be helpful in providing          11. Ward SK, Roenigk HH, Gordon KB. Dermatologic
                                                                                     manifestations of gastrointestinal disorders. Gas-
                        pain relief.24 Selective serotonin reuptake                  troenterol Clin North Am 1998;27:615-36.
                        antagonists may be less effective than tricyclic         12. Simonet WT, Saylor HL, Sim L. Abdominal wall
                                                                                     muscle tears in hockey players. Int J Sports Med
                        antidepressants for the relief of chronic pain.              1995;16:126-8.
                                                                                 13. Lauder TD, Moses FM. Recurrent abdominal pain
                        Resources and Referrals                                      from abdominal adhesions in an endurance triath-
                                                                                     lete. Med Sci Sports Exerc 1995;27:623-5.
                           Family physicians should be able to diag-             14. Longstreth GF. Diabetic thoracic polyradiculopathy:
                        nose and treat many patients with clear-cut,                 ten patients with abdominal pain. Am J Gastroen-
                        localized abdominal wall pain. Alternatively,                terol 1997;92:502-5.
                                                                                 15. Peleg R, Gohar J, Koretz M, Peleg A. Abdominal
                        patients can be referred to a pain treatment                 wall pain in pregnant women caused by thoracic
                        center or a pain treatment subspecialist. These              lateral cutaneous nerve entrapment. Eur J Obstet
                        resources can be located through organiza-                   Gynecol Reprod Biol 1997;74:169-71.
                                                                                 16. Hall PN, Lee AP. Rectus nerve entrapment causing
                        tions such as the American Pain Society (4700                abdominal pain. Br J Surg 1988;75:917.
                        W. Lake Ave., Glenview, IL 60025; telephone:             17. Hughes GS, Treadwell EL, Miller J. Syndrome of the
                                                                                     rectus abdominis muscle mimicking the acute
                        847-375-4715; Web site: www.ampainsoc.org)                   abdomen. Ann Emerg Med 1985;14:694-5.
                        or the American Academy of Pain Manage-                  18. Rutgers MJ. The rectus abdominis syndrome: a case
                        ment (13947 Mono Way #A, Sonora, CA                          report. J Neurol 1986;233:180-1.
                                                                                 19. Knockaert DC, D’Heygere FG, Bobbaers HJ. Ilioin-
                        95370; telephone: 209-533-9744; Web site:                    guinal nerve entrapment: a little-known cause of
                        www.aapainmanage.org).                                       iliac fossa pain. Postgrad Med J 1989;65:632-5.
                                                                                 20. Simons DG, Travell JG, Simons LS. Abdominal muscles.
                                                                                     In: Travell & Simons’ Myofascial pain and dysfunction:
                        The authors indicate that they do not have any con-
                                                                                     the trigger point manual. Vol. 1. Upper half of body.
                        flicts of interest. Sources of funding: none reported.       2d ed. Baltimore: Williams & Wilkins, 1999:940-70.
                                                                                 21. Ling FW, Slocumb JC. Use of trigger point injec-
                        REFERENCES                                                   tions in chronic pelvic pain. Obstet Gynecol Clin
                                                                                     North Am 1993;20:809-15.
                        1. Hershfield NB. The abdominal wall. A frequently       22. Mehta M, Ranger I. Persistent abdominal pain. Treat-
                           overlooked source of abdominal pain. J Clin Gas-          ment by nerve block. Anaesthesia 1971;26:330-3.
                           troenterol 1992;14:199-202.                           23. Hong CZ. Lidocaine injection versus dry needling to
                        2. Gallegos NC, Hobsley M. Abdominal wall pain: an           myofascial trigger point. The importance of the
                           alternative diagnosis. Br J Surg 1990;77:1167-70.         local twitch response. Am J Phys Med Rehabil
                        3. Thomson H, Francis DM. Abdominal-wall tender-             1994;73:256-63.
                           ness: a useful sign in the acute abdomen. Lancet      24. McQuay HJ, Moore RA. Antidepressants and
                           1977;2(8047):1053-4.                                      chronic pain. BMJ 1997;314:763-4.

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